Pasta filata refers to a type of cheese where curds are heated and stretched or kneaded before being moulded into the desired shape. The resulting product has elasticity, and stretches when cooked or melted. Some of the cheeses in this family include mozzarella, provolone and string.
It is well known to produce a cheese of this type, that is, a cheese having a plastic pliable homogenous stringy structure, using additives which soften casein and thereby improve the elasticity of the end product. In one particular well known process, curd is churned in hot water for a predetermined time to cook the curd, which is then kneaded and stretched to develop the pasta filata cheese. In this process, which may be conducted either as a batch process or as a continuous process, the curd is immersed in the hot water to provide even heating thereof, the water generally being heated directly or indirectly by steam or other means. With this process, however, some fat and soluble protein from the cheese curd tends to be lost from the cheese matrix and combine with the water. Thus, not only is fat and protein lost from the product but the effluent is contaminated with these products.
Further, commonly, the fat and soluble protein in the water burns on the water heat exchanger thereby imparting an undesirable contaminant to the water which then contaminates the cheese product both physically, in the form of small, black particles, and in the taste. The heat exchanger also, therefore, requires regular cleaning, and there is a need to constantly replenish the water.
Still further, the water used in the process dissolves salt from the curd. Thus, the waste water, or effluent, from the process is contaminated with substantial impurities which makes it unsuitable for direct discharge or re-use without treatment to remove the contamination. The waste water must therefore be subject to a relatively expensive reprocessing if the water is to be reused as irrigation water or the like. While fat is often recovered for reuse, the remaining dissolved solids are a major loss to the manufacturing and a major trade waste problem also. In many places, the effluent water constitutes a substantial environmental problem and the reprocessing thereof adds substantially to the total process costs.